Support for induction heating coils



H. A. STRICKLAND, JR 2,423,054

SUPPORT FOR INDUCTION HEATING COILS Filed Sept. 1, 1943 2 Sheets-Sheet 1 \ll MM n .D B mm W M 4 H V 0 4 w/ w fil m h H HI a L 9 W E253 M M w 4/ ///f 5 a June 24, 1947.

June 24, 1947. H. A. STRICKLAND, JR 2,423,054

SUPPORT FOR INDUCTION HEATING COILS Filed Sept. 1, 1945 2 Sheets-Sheet 2 lllllll lllll 5 V I INVENTOR 5 44mm -Q.Scrid land,lr.

awn W I ATTORNEY Patented June 24, 1941 SUPPORT FOR INDUCTION HEATING COILS Harold A. Strickland, In, Detroit, Mich., assignor,

by mesne assignments, to The Budd Company, Philadelphia, Pa., a. corporation of Pennsylvania Application September 1, 19 i3, Serial No. 500,772

2 Claims.

This invention relates to induction heating apparatus and more particularly to heating apparatus for workpieces of non-cylindrical or irregular shape.

the plates by screw bolts H. The top plate [2 is illustrated as having an aperture I8 centrally located to receive the workpiece l9 shown in dash outline. At spaced points around the periphery of this aperture i8 are dependent guide bars 20 In the heat treatment of cylindrical workpieces for preventing transverse displacement of the a cyiindricallywound induction heating coil is conworkpiece after insertion within the opening it. veniently and usually employed, the same having The weight supporting means for the workpiece a horizontal axis and the workpiece being inwhich in the form illustrated is a shell having a sorted at the side of the furnace into the coil for conical nose 2|, is a cylindrical member 12 the heating operation. In the case of certain able through the aperture 23 formed in the cennon-cylindrlcal shapes particularly where only ter of the base plate II and adjustably held in a section of the workpiece is to be heated, the vertical position within the casing by means of horizontal furnace is poorly adapted for proper the rigid clamp The pportin m m r 22 Placing a d heating of the workpiece. Moreover extends upwardly a short distance within the in many cases it is undesirabletosupport the work- 15 casing. The upper end of the member is preferpiece through the coils as this involves a comably divided by axially formed openings into plicated mechanical structure, as well as conquadrants an a the extreme op o t tributing to the distortion of the coil shape. t c t portion is y to form a An important object of the present invention ical area 6| adapted to receive the nose tip 2| of is to provide a furnace for inductive heating of the workpiece. It thus appears that when the a workpiece in which the support of the worknose of the workpiece rests in the conical s ppiece is entirely independent of the coil strucp area 5! o t e member t e t re ei ht ture. Another object of the invention is to proof the workp s borne y this member and thet vide a support for a workpiece which will permit by adjustment of clamp 2 the workpiece m y radial adjustment of the workpiece in relation 25 move up or down in relation to the base to secure to the induction heating coil for variation of the the desired position in relation to the heating heating effect. An object of the invention also is 0011- to provideasimplified jig arrangement which may e he ting coil in the part a Showing of be readily modified to support a heating,coil of Fig. l is shaped to correspond with the contour any desired contour with particular adaptation 30 of the nose of the shell i9 and consists of a numfor the supporting of a workpiece having urvi ber of turns 36 of a circular hollow conductor havlinear areas. An additional object is to provide s a r ua ly decreasing d m t r, of tu Propositive holding means for the turns of the heatd s to t e t p or the nose. The final ing coil in relation to the coil jig. An object also nose turn 31 f the coil terminates ar a dlv is to provide a coil support in which the support 35 om t e tip. so that the tip 2i is exposed thro h area afforded the coil turns increases approxithe end coil for engag with the Support lv as t e weishtor the coil. Other objects, member 22. I will appear on consideration of the following de- The specific iig arrangeme t fo Support Of t e scriptlon or the form of the invention which may heating @011 comprises f pairs f ally be preferred and of the accompanying drawings, positioned p s 25, 26, 21 and 28, each p in which: being positioned an equal distance around the Fig. 1 is an elevational, view partly in section periphery of the C011, Opposite P s be g n showing the heating apparatus; co-pl flr relationship. The support plate 29 Fig. 2 is a plan view of the heating coil with of h a is b y triangular i s ap with the furnace casing removed; a narrow section 3| at the top and a broad Fig. 3' is an elevationof the plan view of Fig. 2, Section 32 adjacent the basee b se ends 32 of these plates rest upon the base plate 5 and Fig 4 1 a cti through t k support b are attached thereto by angle bars 33, the screws along lines 4-4 of Fig. 1. being inserted from the bottom side of the base Refe ring t F1g 1 th i di d a furnace plate and also through the vertical section of the casing in of rectangular construction and having angle bars to ho the pl ri in D 9. base plate H, a top plate I2 and side plates tioh- The inner edge 34 of each supp t pl l3, II and IS, the front side plate not being illusis stepp d beg nning adjacent the top of the plate trated. These plates are rigidly attached todown to approximately the end of the shell nose. gether by means of angle brackets l6 secured to These steps 35 are of small width at the top but increase in width progressively toward the base, so thatthe turns 36 of the coil which are adapted to seat in the notches formed by these steps 35 receive more of the width of the conductor toward the lower section of the stepped construction. Thus the lower steps of the supporting plates are adapted to receive more of the weight of the heating coil than the upper steps.

In order to insure a rigid holding of the turns 36 of the coil in the notched steps of the support, use is made of bolts 38. These bolts are placed between the adjoining support plates 25 of each pair with one end 35 silver soldered or otherwise attached to the conductor turn and the other extending beyond the outer edges of the support plates where they are attached by means of washers 4| overlying the two support plate edges and screw nuts 42 to bind the bolt in place. As more clearly shown in Fig. 3 in dashed outline, the bolts are applied to displaced sections of the coil and with the exception of the three upper bolts, are inclined downwardly toward the outer side of the support plates 25. Also the lower outer edges of the support plates are notched as at 43, so that the holding washers of the plates engage the edges at right angles to the bolt axis. This angular positioning of the lower bolts of the structure insures positive engagement of the turns of the coil in the various notches of the stepped edge. The holding bolts 44 adjacent the upper turns are horizontal, since in this section the turn weight is relatively small. There is thus provided, in quadrature, spaced supporting means for the coil which is of utmost simplicity and which may be readily and easily moved to suit the configuration of the coil as desired. The material of these supporting edges is of insulation stock such as an asbestos panel board, Transite, or similar compositions that are heat resistant and possess an adequate rigidity for the purpose intended. Cross bolts 8 are used to clamp the support plates 28 together.

The ends of the coil from the top and bottom thereof are led outwardly from the same through clamp supports 50 and El. Each support consists of a bar of insulation material positioned adjacent the top of the support plates on either side thereof, these bars being axially apertured to receive a bolt 52 having screw threaded ends. The ends 53 of the bars are curved to receive couplings 54 for the conductors, and clamps 55, held in position by the nut ends of the bolt, normally hold the coupling and the associated conductor in fixed position. The coupling as shown in Fig. 1 extends beyond the support plates to appropriate supporting and water coupling means 56 external to the casing l0. Electrical connections by clamps or the like may be made on the couplings 5| or otherwise as desired.

It is now apparent that in the arrangement as described, the workpiece such as the shell may be inserted in the opening [8 with the support member 22 holding the weight of the same; that the coil 30 encloses the end of the shell with the exception of the extreme tip 2| and conforms in curvature thereto and while in close proximity to the shall does not contact with it at any point, thus permitting but not requiring freedom from insulation on the conductor turns; that the jig unit consisting of only four spaced members 29 rigidly fixed with reference to the workpiece, is provided with steps having widths designed to take care of increasing coil weight proceeding toward the base and is formed of a material easily workable to conform to any desired coil shape.

The independence of the coil with reference to the workpiece not only permits ireedom from insulation of the turns and therefore increased simplicity but also a variation in the spacing of the workpiece and heating unit by means of the adjustable support member 22, so that the degree of heating application may be controlled to a considerable extent by variation in spacing between workpiece and coil. It is of importance to observe also that in the case of uninsulated or non-insulated conductors flxity of position of the conductor turns is most essential to prevent short circuiting; and that this flxity of positioning is obtained in the construction as shown by the notched steps and the angularly displaced bolts which hold the coil structure at the outer limits of the notches, these bolts being positioned along the entire length of the coil.

As shown in Fig. 1 of the drawing the conductor of the coil is hollow to receive coolant. The conductor shown is circular in cross section but as desired the conductor may be square in section or any other desired shape.

Modifications in the general or specific arrangement of the structure may of course be made and hence no limitation is implied by the illustrated embodiment, other than as required by the scope of the claims hereto appended.

What is claimed is:

i. In a heating apparatus, a base. a heating coil. right angled support plates extending radially from a common center on said base for supporting said coil, said plates being in pairs and having their inner edges stepped for the reception of the individual coil turns. and means for fixedly holding said turns in position in said steps, said holding means comprising bolts positioned between said plates and secured to individual coil turns at one end and to the outer edges of the pairs of supporting plates at the other end, the point of plate edge attachment for the most of the bolts being below the plane of the respective associated coil turn.

2. In a heating apparatus, a base, a heating coil, support plates extending lengthwise of the coil axis and perpendicularly from the plane of the base and radially from a common center on said base for supporting said coil, said plates being in pairs and having their inner edges stepped for the reception of the individual coil turns, and a means for fixedly holding said turns in position on said steps, said holding means comprising bolts extending outwardly and downwardly toward said base between said plates and having one end attached to a coil turn and the other end to the edge of said'pair of plates.

HAROLD A. STRICKLAN'D, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,680,595 Davis Aug. 14, 1928 1,811,213 Rohn June 23, 1931 2,052,649 Patterson Sept. 1, 1936 2,321,189 Dravneck June 8, 1943 2,337,258 Limpel Dec. 21, 1943 1,279,313 Finnie Sept. 17, 1918 FOREIGN PATENTS Number Country Date 422,984 Great Britain Jan. 23, 1935 

